How to prevent heat treatment deformation of precision molds?

Author: MULAN -Plastic Molding Manufacturer

In the process of heat treatment, precision molds are often deformed. In order to prevent this bad phenomenon, as long as we grasp the law of deformation, analyze the reasons for it, and use different methods to prevent the deformation of injection molds, it can be reduced, and it is also possible controlling. Generally speaking, the heat treatment deformation of precision and complex molds can be prevented by the following methods organized by injection mold manufacturers. (1) Reasonable selection of materials.

For precision and complex molds, micro-deformation mold steel with good material (such as air-quenched steel) should be selected. Reasonable casting should be carried out for mold steel with severe carbide segregation, and solid solution double refinement heat treatment can be carried out for large and uncastable mold steel. . (2) The design of the mold structure should be reasonable, the thickness should not be too disparate, and the shape should be symmetrical. For the mold with large deformation, the deformation law should be grasped, and the machining allowance should be reserved. For large, precise and complex molds, a combined structure can be used. (3) Precision and complex molds should be pre-heated to eliminate residual stress generated during machining.

(4) Reasonably select the heating temperature and control the heating speed. For precision and complex molds, slow heating, preheating and other balanced heating methods can be adopted to reduce the heat treatment deformation of the mold. (5) Under the condition of ensuring the hardness of the mold, try to use pre-cooling, graded cooling quenching or warm quenching process. (6) For precision and complex molds, vacuum heating quenching and cryogenic treatment after quenching should be used as much as possible if the premise permits.

(7) For some sophisticated and complex molds, pre-heat treatment, aging heat treatment, quenching and tempering nitriding heat treatment can be used to control the precision of the mold. (8) When repairing defects such as mold sand holes, pores, and wear, use cold welding machines and other repair equipment with small thermal impact to avoid deformation during the repair process. There are many methods of heat treatment process operation, including such as plugging holes, binding holes, mechanical fixing, appropriate heating methods, accurate selection of the cooling direction of the mold and the direction of movement in the cooling medium, etc. Reasonable tempering heat treatment process is also to reduce precision and complexity. Effective measures for mold deformation.